Learn Hardcore Indonesian: Kami membaca buku tentang perang di perpustakaan.

present simple: We read a book about war in the library (regularly).
present continuous: We are reading a book about war in the library (right now).
past: We read a book about war in the library (yesterday / earlier).
even future, depending on context.

To make the time clearer, speakers usually add time expressions:

Kemarin kami membaca buku… – Yesterday we read a book…
Sekarang kami sedang membaca buku… – Right now we are reading a book…
Besok kami akan membaca buku… – Tomorrow we will read a book…

So membaca itself is tenseless; context or extra words show when the action happens.

Why is it membaca and not just baca? When do I need the me- prefix?

Baca is the root verb, meaning “to read.”

The form membaca is the active verb with the prefix me- (plus an extra m due to sound rules). In general:

me- + root → active verb, usually “doing” something to an object
- makan (root) → memakan (to eat [something], more formal)
- baca (root) → membaca (to read [something])

In everyday speech:

You very frequently see membaca in neutral or formal style.
You can also see baca used directly as a verb in informal speech (especially spoken or casual writing):
- Kami baca buku… – casual.

In a “standard sentence” like Kami membaca buku tentang perang di perpustakaan, membaca is the textbook‐style, grammatically complete active verb.

Does di perpustakaan mean the war is in the library or that we are reading in the library?

In this sentence, di perpustakaan is understood to modify the activity of reading, not the war:

Kami membaca [buku tentang perang] [di perpustakaan].
→ We read a [book about war] [in the library].

The natural grouping is:

buku tentang perang = a book about war (one noun phrase)
di perpustakaan = in the library (place where reading happens)

If you really wanted to say “a book about a war that is in the library,” you’d need a more complex structure, e.g.:

buku tentang perang yang terjadi di perpustakaan
→ a book about the war that happened in the library

So by default, di perpustakaan goes with the verb membaca, not with perang.

What exactly does tentang mean, and can I replace it with other words like mengenai?

tentang means “about” / “on the subject of.”
So buku tentang perang = a book about war.

You can often replace it with:

mengenai – also “about, regarding”
- buku mengenai perang – a book about war
perihal – “regarding, concerning” (more formal and less common in everyday speech)

In most everyday contexts:

tentang and mengenai are interchangeable.
tentang sounds very neutral and common in modern usage.

So Kami membaca buku tentang perang di perpustakaan is probably the most natural everyday form.

There’s no “a” or “the” before buku. How do articles work in Indonesian?

Indonesian has no direct equivalents of English “a/an/the”. The bare noun buku can mean:

a book
the book
simply books in a general sense, depending on context.

Examples:

Saya membeli buku.
→ I bought a book / I bought the book (depends on context)
Kami membaca buku tentang perang.
→ We read a book about war or We read the book about war.

If you really want to emphasize “a single book”, you can add a classifier like sebuah:

Kami membaca sebuah buku tentang perang di perpustakaan.
→ We read a (single) book about war in the library.

But in many cases, Indonesian just leaves the noun bare and lets context do the work.

How do I show plural here? Is buku singular or plural?

buku by itself is number‑neutral: it can be singular or plural.

To emphasize plural, you have several options:

Reduplication of the noun:
- buku-buku – books (more than one)
- Kami membaca buku-buku tentang perang di perpustakaan.
  → We read books about war in the library.
Using a number + classifier:
- tiga buah buku tentang perang – three books about war
- beberapa buku – some books
Context only: often enough for native speakers.

So the original sentence could be understood as “a book” or “books” depending on context; grammatically, buku alone isn’t forced into singular or plural.

Is the word order fixed? Can I move di perpustakaan to the front?

The basic, neutral order is Subject – Verb – Object – (Adverbials):

Kami (S) membaca (V) buku tentang perang (O) di perpustakaan (Adverbial).

But you can move the place phrase di perpustakaan to the front, usually for emphasis or style:

Di perpustakaan kami membaca buku tentang perang.

This would sound like:

In the library, we read a book about war.

The meaning is the same; the difference is just which element you highlight. Word order in Indonesian is more flexible than English, especially for adverbials like time and place.

Could I drop kami and just say Membaca buku tentang perang di perpustakaan?

Yes, in informal speech or when the subject is clear from context, Indonesian often drops the subject pronoun:

(Kami) membaca buku tentang perang di perpustakaan.

Without kami, the sentence becomes less specific — it could mean:

[We/they/people] read a book about war in the library.

Some possibilities:

In conversation where it’s obvious who “we” is, people might just say Membaca buku tentang perang di perpustakaan as a fragment or continuation of a previous sentence.
In written instructions or notes, subjectless sentences are quite common.

For clear, standalone, textbook‐style sentences, it’s good to keep kami.

What’s the difference between di perpustakaan and ke perpustakaan or pada perpustakaan?

These prepositions have different roles:

di = at/in/on (location, where something is)
- di perpustakaan – in/at the library (location)
ke = to/toward (movement, where you go)
- ke perpustakaan – to the library (direction)
pada = at/on/in, but mostly with abstract or non‑physical locations, or in formal writing
- pada hari Senin – on Monday
- pada zaman perang – in the time of war

So:

Kami membaca … di perpustakaan.
→ We are already at the library, and reading there.
Kami pergi ke perpustakaan.
→ We go to the library.

Saying pada perpustakaan would be unusual and generally incorrect for physical location; use di perpustakaan.